NATURAL SCIENCES OE PHILADELPHIA. 281 



dentary bone, and especially with Portheus in the irregular sizes 

 of the teeth. The crowns are, however, compressed and knife- 

 like, and closely similar to those of Saurocephalus. The typical 

 species was called Erisichthe nitida, and was stated to have been 

 discovered in the cretaceous formation of Kansas, near to the 

 Solomon River, by Prof. B. F. Mudge. The enamel of the teeth 

 is smooth and glistening, and their outline acuminate and 

 rather elongate. In the anterior part of the jaw are two teeth 

 much larger than the others, separated by a small tooth. The 

 posterior of these is much compressed, while the anterior is oval 

 in section, with one angular edge. Length of the restored skull 

 between one and two feet. 



It was added that the Portheus angulatus, Cope, probably 

 belongs to the genus Erisichthe, and that it differs from E. nitida 

 in its greater size and other features. The genus was further 

 stated to be abundant in certain formations of the Southern States, 

 and in the English chalk. Isolated specimens of large teeth from 

 the latter had been referred to the genus Saurocephalus in the 

 Poissons Fossiles, which could not be distinguished from those of 

 the genus newly described. 



December 24. 

 The President, Dr. Ruschenberger, -in the chair. 

 JFen members present. 



December 31. 



The President, Dr. Ruschenberger, in the chair. 



Twenty members present. 



The following reports were read, and referred to the Publication 

 Committee: 



THE LIBRARIAN'S REPORT. 



The Librarian respectfully reports that the number of addi- 

 tions to the library from January to December, 1872, inclusive, 

 amounts to 1488. 



Of these 250 were volumes, 1230 pamphlets and parts of periodi- 

 cals, and 8 maps and charts ; 1135 were octavos, 310 quartos, 20 

 duodecimos, 15 folios, and 8 maps. 



They were derived from the following sources : 



Societies 106, Editors 139, Authors 188, Wilson Fund 67, Isaac 

 Lea 12, Imperial Botanical Garden of St. Petersburg 11, Thomas 

 19 



